Shoe lasting machines

ABSTRACT

A SHOE LASTING MACHINE IN WHICH A STOP LIMITS MOVEMENT OF WIPERS TO AN INTERMEDIATE POSITION IN WHICH AN UPPER HAS BEEN WIPED OVER A SHOE BOTTOM ONLY ENOUGH TO HOLD AN INSOLE AGAINST A LAST BOTTOM, AND A PRESSURE PLATE WHICH PREVIOUSLY HELD THE INSOLE IS THEREAFTER RETRACTED AND CONTROLS CONTINUED MOVEMENT OF THE WIPERS.

May 25, 1971 R. FICHTNER 5TM- SHOE LASTING MACHINES 2 Sheets-Sheet 1 Filed Jan. 19. 1970 fw@ ci? hbo MKM Tw mmm RWUWUJW M0? 25; 1971 R. FlcHrNER F-'I'AL SHOE LASTING MAGHINES 2 Sheets-Sheet l Filed Jan. 19. 1970 man@ United States Patent O" 3,579,691 SHOE LASTING MACHINES Rudi Fichtner, Ober Horgern, and Wilhelm Klein, Frankfurt am Main, Germany, assignors to USM Corporation, Boston, Mass.

Filed Jan. 19, 1970, Ser. No. 3,912 Int. Cl. A43d 21/00 U.S. Cl. 12-12A 5 Claims ABSTRACT OF THE DISCLOSURE A shoe lasting machine in which a stop limits movement of wipers to an intermediate position in which an upper has been wiped over a shoe bottom only enough to hold an insole against a last bottom, and a pressure plate which previously held the insole is thereafter retracted and controls continued movement ofthe wipers.

4BACKGROUND OF THE INVENTION This invention relates to improvements in machines for lasting the ends of shoes in which an upper and an insole are loosely assembled on a last. An end of the insole is held by a pressure plate against the bottom of the last adjacent its periphery and wipers last the upper about the adjacent end of the last and lay the margin inwardly over the insole, the pressure plate being automatically retracted out of interfering relationship with the wipers.

DESCRIPTION OF THE PRIOR ART The lasting of shoes is usually elected by wipers which last the shoe upper about an end of a last and lay the margin of the shoe upper inwardly over the bottom of an insole. The insole may be initially held against the last bottom by a pressure plate which engages the insole adjacent its periphery. Care must be taken that the pressure plate is retracted during the advance of the wipers so that the wipers do not strike the pressure plate and damage either the wipers or the plate. In known lasting machines, the pressure plate is actuated at the start of the Wiper advance over the insole edge so that the plate is retracted out of the path of the wipers. It is common to provide a safety device which stops the power supply for the advance of the wipers when they have reached a position just over the edge of the insole and to reactivate the power supply when the pressure plate has been retracted to a noninterfering position. Usually, retraction of the pressure plate is commenced automatically and if the plate fails to be retracted the wipers frequently are stopped before they have moved inwardly enough to retain the insole against the last bottom. It may also happen that the pressure plate drops prematurely releasing the power supply for the wipers which then may displace the margin of the insole as they advance, resulting in an improperly lasted shoe. Under normal conditions, when the pressure plate is not delayed in its retraction, it drops immediately with the advance of the wipers so that the second actuation of the power supply is effected during the advance of the wipers. In this way the v wipers are not stopped at all in an intermediate position and the pressure plate may drop prematurely before the wipers move inwardly over the edge of the insole. Thus the insole margin may lift sufficiently so as to be struck by the advancing wipers rather than to be held down against the last bottom.

SUMMARY OF THE INVENTION Accordingly, it is an object of the invention to eliminate the above disadvantages and to insure :that the edge of the insole is held against the last bottom while maintaining security against the wipers striking the pressure plate. To this end, initial movement of the wipers is limited by a ice stop which engages a portion of the wiper actuating mechanism. Thus the wipers are stopped in an intermediate position where they have just passed inwardly over the edge of the insole with the partially overwiped upper margin holding the insole against the last bottom. Continued movement of the wipers to complete the overwiping of the upper margin against the last bottom is initiated only after the pressure plate has arrived at a retracted location out of interfering relationship with the Wipers.

According to a further feature, the location of the stop is adjustable so that the intermediate stop position of the wipers can be varied for different shoes to insure that the wipers have passed sufficiently over the edge of the insole to hold it against Ithe last bottom while the pressure plate is retracted. In this manner striking of the wipers against the pressure plate is positively prevented since further advancing movement of the wipers is dependent upon retraction of the pressure plate. To this end, the mechanism for retracting the pressure plate is provided with a signal transmitter such as a switch which is actuated only when the pressure plate has arrived at its retracted pos1t1on.

The above and other objects and features of the invention together with novel details of constructions will now be described with particular reference to the embodiments shown in the drawings and thereafter pointed out in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, an insole 8 of a shoe 9 to be lasted rests on a shoe support 10 which is of sutciently small size that it will not interfere with operation of the wipers of the machine even when in fully closed condition. The shoe to be lasted may be held in place on the support by commonly known devices, not shown. Adjacent its margin the insole S also rests on a pressure plate 11 arranged to partially surround the shoe support 10. The pressure plate may be provided with channels 16 through which adhesive in uid form is pumped for application to the lasting margin of the insole. The machine is provided with wipers 7 adapted to wipe the shoe upper inwardly over the shoe bottom, the wipers being supported in a holder 5 arranged to be actuated by a head 17 connected to the holder by a member 6. The head 17 is secured to the end of a rod 18 connected to a piston 4 which is moved back and forth in a cylinder 19 by hydraulic or pneumatic forces. The rod 18 extends through the piston to the left, as seen in FIG. l, and at its end has secured thereto a stop 1. As the wipers are moved to the right, as seen in FIG. 1, to engage the shoe upper the stop 1 is carried along by the rod 18 until it reaches the position indicated by broken lines where further movement is prevented by a block or wedge 2,. The wedge is carried by the lower end of a rod which extends from an actuating device 3 such as an electrically operated solenoid or a Huid operated motor. g

The pressure plate 11 is carried on the upper end of a rod 20 of a piston 21 movable heightwise in a cylinder 22. In its initial condition, the pressure plate is in the position shown in FIG. l where it holds the margin of the insole against the last bottom. By admission of pressure fluid through a line 28 in the upper end of the 3 cylinder 22, the pressure plate may be retracted to the position shown in broken lines.

To operate the machine a control motor 12 is actuated in any convenient manner such as by a treadle or control button (not shown). A control member 13 is advanced by the motor 12 at a predetermined speed, whereupon a cam surface on the member engages an actuator 23 of a valve 14. This connects a source of uid pressure to a line 24 leading to one end of the cylinder 19 so the piston 4 is moved to the right as seen in FIG. l. The piston through the rod 18 and head 17 advances the wipers 7 until the stop 1 on the left end of the rod 18 engages the wedge 2. At this time the wipers assume the intermediate position indicated by broken lines in which the margin of the upper is moved just over the edge of the insole 8. Further advancing movement of the wipers is pre-vented by engagement of the stop with the wedge. During this operation, the control member 13 has continued to advance at a controlled rate and a cam surface on the member engages an actuator 27 which operates a valve 15. Actuation of the valve connects the feed line 28 to the main source of fluid pressure, causing the pressure plate 11 to be retracted by downward movement of the piston 21. The lower end of the piston rod extending below the cylinder 22 is provided with a cam 34 which actuates a switch 26 when the pressure plate is retracted sufliciently out of the path of movement of the wipers. The switch is connected to a terminal A of the control device 3 which is actuated at this time to move the wedge 2 out of interfering relation with the stop 1. The wedge 2 is provided with an inclined surface 29 which mates with a corresponding surface on the stop 1 so the wedge may be easily retracted. Since at this time tluid pressure has been continuously applied through the line 24, the wipers are again advanced so the margin of the upper is completely wiped over the insole bottom.

In FIG. 2 the above described operations are represented in the form of a timing diagram. At the time T1, movement of the control member 13 is commenced. At the time T2, the element has engaged actuator 23 and operated the Ivalve 14 commencing the advancing movements of the wipers 7. The advance of the wipers is stopped in intermediate position at the time T3 when the stop 1 engages the wedge 2. Continued movement of the control member 13 until the time T4 causes actuation of valve 15 through the actuator 27. Thus, at time T4, after the wipers have stopped in their intermediate position at time T3, the pressure plate is retracted. Thereafter the cam 34 actuates the switch 26 at the time T5 when the plate is retracted suiciently out of the path of the wiper movement and the wedge 2 is retracted, permitting con tinued movement of the wipers until the time T6. Thus it may be seen that the retracting mechanism for the pressure plate 11 is controlled to cause retraction of the plate after a certain delayed time determined by the interval between the time T2 and the time T4. This delay time begins with the start of movement of the wipers 7 and ends after the stop 1 engages the wedge 2 which occurs at the time T3 and insures that the wipers 7 will have moved inwardly over the insole edge to hold the insole against the last bottom before the pressure plate is retracted.

FIG. 3 shows an arrangement which corresponds in mechanical structure to the arrangement shown in FIG. 1. The latter arrangement however operates on a different control principle whereby retraction of the pressure plate 11 is initiated positively when the stop 1 engages the wedge 2 rather than relying on a delayed time sequence. To this end, the stop 1 is provided with a cam surface adaptedvto acuate a switch 30 which energizes a relay 31 operatively connected to a valve 32. The valve 32 upon actuation connects the feed line 28 to line pressure so that retraction of the pressure plate 11 is commenced only when the stop 1 engages the wedge 2 and the wipers 7 are in their intermediate position and holding the insole 4 against the last bottom. Retraction of the wedge 2 is caused in the same manner as in the control mechanism shown in FIG. 1 when the cam 34 actuates switch 26 and causes the actuator 3 to be energized.

A delay element 33 is connected between the switch 30 and the relay 31 so that a time delay is caused between arrival of the wipers at their intermediate position and the retraction of the pressure plate. This gives suicient time vfor adhesive to be pumped through the channel 16 in the pressure plate and on to the insole bottoml before the wipers are again advanced.

The operation of the machine employing the control system of FIG. 3 is illustrated by the timing diagram shown in FIG. 4. At the time T1, pressure iluid is introduced to cylinder 19 and operation of piston 4 begins the initial advance of the wipers. At the time T2 the stop 1 engages the wedge 2 causing actuation of the switch 30 when the wipers arrive at their intermediate position. This is followed by the delay time determined by the delay element 33 up to the time T3 when actuation of relay 31 and valve 32 causes the pres-sure plate 11 to be retracted. At the time T4 the switch 26 is actuated =by the cam 34 causing the wedge 2 to be retracted. From the time T4, the wipers continue their advance until the time T5 when the upper margin is fully wiped over the insole |bottom.

As mentioned above in relation to either of the control systems according to FIG. l or FIG. 3, the arrangement is such that the wipers have just moved over the edge of the insole when they are stopped in their intermediate position. The wipers thus hold the insole against the last bottom through the partially overwiped upper before the pressure plate is retracted fromthe insole. This insures that the margin of the insole cannot be displaced while insuring that the pressure plate is moved out of the path of the wipers, avoiding potential damage to the shoe as well as damage to the wipers and/or the pressure plate.

Having thus described our invention, what we claim as vnovel and desire to secure by Letters Patent of the United States is:

1. In a shoe lasting machine having a member for holding an insole against the bottom of a last and wipers movable along a path adapted to lay the margin of a shoe upper on the last inwardly over the bottom of the insole, the improvement comprising a stop for limiting initial movement of the wipers to an intermediate position over the edge of the insole suiiicient to hold the insole against the last bottom, means effective after the wipers arrive at said position to retract the member from the insole to a location out of the path of movement of the wipers, and means actuated after arrival of the member at said location for releasing said stop to permit continued wiping movement of the wipers.

2. A machine according to claim 1 in which the stop moves with the wipers and engages a retractable block to stop the wipers in said intermediate position.

3. A machine according to claim 2 in which the retractable block is adjustable to vary the intermediate position of the Wipers. ai

4. A machine according to claim 2 in which a devic associated with the member retracting means causes retraction of said block when the member has arrived at said location.

5. A machine according to claim 1 in which a control device is actuated by said stop when the wipers are in said intermediate position to initiate operation of said member retracting means.

References Cited UNITED STATES PATENTS 2,479,575 8/1949 Jorgensen 12-12.4 3,268,930 8/ 1966 Rockwell et al. 12-l2.4 3,309,721 3/1967 Jourdan 12--8.8

PATRICK D. LAWSON, Primary Examiner 

